SSM2302: Output overshoot.

Document created by analog-archivist Employee on Feb 23, 2016
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There is about 1.56V overshoot at the output. Is it normal?
Test condition is in below:  Source is from mp3 played by a computer.   Load
is speaker, one is 8Ohm, another is 100Ohm. It is connected between the Vout+
and Vout- in series. Supply voltage is single 5V.


the ringing is due to too long GND lead of a probe. An alligator clip can not
be used.
The overshoot around 750mV  is reasonable. A switching output stage has dead
time which mean either high side and low side switch off.
During the time, body diode is forward biased by current through the load, and
the output voltage becomes higher than VDD or lower than GND by Vf of the body
This is a common behavior for any system which use a switching output state.
(i.e. DC-DC converter, class-D amplifier, etc.)